Expansible and contractible tool



i. H. AUBLE.

EXPANSIBLE AND CON'IRACTIBLE TOOL.

APPLICATION FILED APR. I4, |911.

1,332,455. Patented Mar. 2, 1920.

IIIIIIIIIIIIIIIIIIIIIIIIIIIIII qitlltll Jai/ins H. AUBLE,

OF CINCINNATI,

OHIO.

EXPANSIBLE AND CONTRACTIBLE TOOL.

Application led April 14, 1917.

To all vwhomy t may concern.'

Be it known that I, JAMES H. AUBLE, a citizen of the United States, anda resident of the city of Cincinnati, in the county of Hamilton andState'of Ohio, have invented certain new and useful Improvements inExpansible and Contractible Tools, of which the following is a full,clear, and exact description, reference being had to the accompanyingdrawings, forming part of this specification.

My invention relates to expansible and contractible tools such asreamers, taps, dies, lathe mandrels, bearings and the like which areformed so that the tool can be expanded or contracted for differentsizes of work. The object of the invention is to produce a machine toolor die holder', or the like, the metal of which shall be adapted to beadjusted as to its working diameter1 for various sizes of work much moreeffectively and with more perfect accuracy than has heretofore beenpossible with the ordinary methods of providing for expansion andcontraction.

Ordinarily in order to provide for various sizes of work, it has beencustomary to form the tool or holder of long strips or sections adaptedto be opened out lengthwise to vary the size by wedges or cones. TWithcutting and other kinds of tools where very accurate work is to beperformed, it is exceedingly dificult to obtain a perfect adjustment forthe exact size required, particularly without throwing the workingsurface of the tool 01T center.

My invention avoids the difficulties incident to the ordinary methods ofadjusting the size, and it consists in its essentials in expanding orcontracting the tool or holder in radial planes, so to speak, instead oflongitudinally. To obtain this result, I form the body of the tool froma strip or bar of suitable metal formed in a spiral with the spiralconvolutions held together or compressed longitudinally so as to formsubstantially a solid body portion of the metal, and the desiredaccurate expansion is obtained by forcing the tool body on a conicalholder, so that as the body of the tool is advanced on the cone, thespiral convolutions will be expanded or contracted by increasing ordecreasing the diameter of the .convolutions.

I have illustrated my invention in the drawings with reference to areamer and a Specification of Letters Patent.

Patented Mar. 2, 1920.

Serial No. 161,973.

tap for interior or exterior thread cutting, but it will be understood,of course, that the novel construction to be hereinafter particularlvpointed out and claimed can be readily adapted to the formation of agreat variety of tools and holders in which it is desirable to expand orcontract the tool body for varying sizes of work.

In the drawings,

Figure l is a side elevation partly in section of the tool blank for anexpansible reamer.

F ig. 2 is a longitudinal section of an extericr thread cutter.

F ig. 3 is a central longitudinal section of my invention as applied toan expansible reamer.

Fig. 4 is a perspective view of a reamer with the flutes spirally cut.

Fig. 5 is a perspective view of the tap embodying my invention.

Fig. 6 is a longitudinal section thereof.

In order to form the blank for an expansi'ble reamer, for example, Itake a. strip of metal of the proper length, rectangular in crosssection, and of such size and thickness as may be suitable for theparticular purpose. For example, for a reainer an inch or an inch and ahalf in diameter, I take a stripone-eighth of an inch thick and onehalfinch wide and wind it on a cylinder or 'mandrel into a spiral coilandbring the coils together, conning it longitudinally and then,annealing to soften the metal so that it will remain permanently in aclosed coil, as indicated in Fig. l, in which l represents the coil ofmetal. A conical hole 2 is then bored out of the coil of a shape tocorrespond to the conical surface of the shank of the reamer upon whichthe body portion is to be mounted. The iiutes are cut and the blank thenretempered, whereupon it is threaded interiorly to correspond to thethreads l cut on the cone shaped end 5 of the shank 6 of the tool.

In the exempliiication of the invention as shown in Fig. 3, the shank ofthe tool is screwthreaded at 7 to receive a lock nut 8 against which thebody of the reamer abuts and the outer end of the shank is also providedwith a screw-threaded portion 9 to hold a locking nut to abut againstthe outer end of the reamer body when it expands beyond the end of thecone shaped portion.

It is evident that with this construction.l by advancing the reamer onthe cone 5, a

very accurate and perfect expansion may be obtained.

-With the body of the reamer constructed as outlined above, it ispossible to provide an expansion reamer with spiral flutes as shown inFig. il, in which the spiral flutes are indicated at 10.

It will be readily seen that the construction above described is equallyapplicable `for a tap for thread cutting as indicated in Figs. 5 and 6,in which ll is the shankof the tap, l2`the body of the tap made up ofspiral convolutions with the bore 13 cone shaped and interiorly threadedto t the threads of the convev portion 14 of the tool. The cutting teeth15 of'tlie tap are given a pitch to correspond to the pitch of thespiral, or rather the pitch of the spiral from which the body of the tapis made is constructed so that cutting teeth will always be formed onthe body of the metal and will not cross any spiral portion. A singletooth for each spiral convolution, or a plurality of teeth may beformed, two of such teeth being indicated in the illustration of the tapshown in Figs. 5 and 6.

For an exterior threader, the spiral 20 (Fig. 2) is cut cylindrical onthe inside and conical on the outside. The 'outside is threaded at 2l,and the inside cut with the thread forming faces 22. A sleeve 23 isprovided having a conical, threaded interior terminating in acylindrical end 24. A shank 25 is provided to t the portion 24, and alock' nut 26 is employed to lock the sleeve in the desired position.Advancing the sleeve on the shank will compress the spiral causing theconvolutions to become smaller and the spiral tool slightly longer,thereby adjustingits working diameter.

It will be evident that the tap can be eX- panded with great accuracy,and with iny` invention applied to the construction of` H taps,theexpansion of the metal as it is advanced on the cone has the effectof bringing the cutting teeth slightly out' of line or in somewhatzigzag position, which presents a much more effective cuttera l/Vhile Ihave not illustrated my invention in connection with other cutting toolsor` structions which readily suggest themselves.

Thus the maiidrels would be `constructed like the reamers, except theworking surface would be smooth and the bearings could be 'made like theexterior thread cutter.

lt is not desired in this application to be 50 construed as mentioningall variations and inodiications which suggest themselves to ine, sinceit is desired here to point. out, describe and `claim the essentialcharacteristic of the tool made up of a spiral. 65

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is

l. A tool comprising a spiral of metal having working surfaces, and aholder for said metal spiral, with correspondingly screw threadedengaging surfaces between the spiral and holder, said spiral having aplurality of threads throughout its length,

whereby the rotation of the metal spiral will adjust the workingdiameter of the tool.

2. A tool comprising a spiral of metal hav ing working surfaces, and aholder for said metal spiral, with correspondingly screwthreadedengaging surfaces between the s0 spiral and holder, said spiral having aplurality of threads throughout its length, whereby the rotation of themetal spiral will adjust the working diameter of the tool, and

a lock nut to hold said tool in adjusted po- 35 sitions.

JAMES H. AUBLE.'

